1. Department of Human Genetics; Leiden University Medical Center; Leiden The Netherlands
2. Department of Medical Statistics and Bioinformatics; Leiden University Medical Center; Leiden The Netherlands
3. Department of Neurology; Leiden University Medical Center; Leiden The Netherlands
4. C.J. Gorter Center for High Field MRI, Department of Radiology; Leiden University Medical Center; Leiden The Netherlands
5. John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine; University of Newcastle; Newcastle upon Tyne UK
6. Dubowitz Neuromuscular Centre; University College London Great Ormond Street Institute of Child Health; London UK
7. Division of Proteomics, School of Biotechnology; KTH-Royal Institute of Technology; Stockholm Sweden
8. Neurochemistry Lab and Biobank, Department of Clinical Chemistry, Amsterdam Neuroscience; VU University Medical Center Amsterdam; The Netherlands